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Author Topic:   How so may RPM'S
Dirt Roller

Total posts: 12
posted June 06, 2004 05:13 PM  
I run a street Stock class mostly GM cars, The engine rules are pretty simple, Any factory Cast Iron intake (mostly Boe Tie high Rise) 60 over max flat top pistons ,450 max lift camshaft any duration no vacuum rule. 2 barrel 4412 un modified holley, stock rear end may be locked stock transmission.
My question, most of the front running cars are turning 6500-7500 RPM's I turn 5200 rpms, I have won 2 features and alot of heats this year, Im second in points so I cannot complain but It seems unless 2-3 other cars brake or wreck out they beat me. they always seem to get me off the corner I talked to a few of them one runs a 410 rear gear w/350trans in 2nd. the others a 256 in 1st, I run a 241 in first, What can I do within the rules to run that gear and turn more RPMS what decides rpms lift, duration, both? My engine runs out of rpms 3/4 down the straights. so More gear most likely will not help me. Someone give me some advice

Dirt Full Roller

Total posts: 66
posted June 06, 2004 06:34 PM  
it seems like they got a bit more torque off the conner try a speed pro 447/447 is aroun 400 ft lbs of torque at 3000 rpms and if your only hitting 5200rpm its like you dont got a good gear id run higher but your running out try lower it may pull further down the strate if you cant get the rpms work with what ya got.. are ss have to run a ristictor plate and the max out at 6000 rpm so the gear the car to pull to the end of the staite.. and a baby cam like a 447 to get off the coner out max lift rule is 550 and the 447 is the one to beat

Dirt Forum Champ
Total posts: 5390
posted June 06, 2004 08:20 PM  
Well I know you're talking about southern theres a lot of room in those street rules to be creative I'm building a motor for my brother nowI'll bet that most of the motors winning most of the time and turning those rpms are in the very grey area they get their power from the heads and don't take it at face value about stock 4412's or stock ignitions use the rules read em close lot of room you need somewhere around a656 gear and an 86" tire on the rear and about an 88 on the rf and 87 on the lf you gotta use light stuff push the book and Smile

[This message has been edited by Flatlander (edited June 06, 2004).]


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